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31.
32.
Klaus Peter Jochum Ulrike Weis Brigitte Stoll Dmitry Kuzmin Qichao Yang Ingrid Raczek Dorrit E. Jacob Andreas Stracke Karin Birbaum Daniel A. Frick Detlef Günther Jacinta Enzweiler 《Geostandards and Geoanalytical Research》2011,35(4):397-429
We present new reference values for the NIST SRM 610–617 glasses following ISO guidelines and the International Association of Geoanalysts’ protocol. Uncertainties at the 95% confidence level (CL) have been determined for bulk‐ and micro‐analytical purposes. In contrast to former compilation procedures, this approach delivers data that consider present‐day requirements of data quality. New analytical data and the nearly complete data set of the GeoReM database were used for this study. Data quality was checked by the application of the Horwitz function and by a careful investigation of analytical procedures. We have determined quantitatively possible element inhomogeneities using different test portion masses of 1, 0.1 and 0.02 μg. Although avoiding the rim region of the glass wafers, we found moderate inhomogeneities of several chalcophile/siderophile elements and gross inhomogeneities of Ni, Se, Pd and Pt at small test portion masses. The extent of inhomogeneity was included in the determination of uncertainties. While the new reference values agree with the NIST certified values with the one exception of Mn in SRM 610, they typically differ by as much as 10% from the Pearce et al. (1997) values in current use. In a few cases (P, S, Cl, Ta, Re) the discrepancies are even higher. 相似文献
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35.
Shitou Wu Gerhard Wrner Klaus Peter Jochum Brigitte Stoll Klaus Simon Andreas Kronz 《Geostandards and Geoanalytical Research》2019,43(4):567-584
Three synthetic reference glasses were prepared by directly fusing and stirring 3.8 kg of high‐purity oxide powders to provide reference materials for microanalytical work. These glasses have andesitic major compositions and are doped with fifty‐four trace elements in nearly identical abundance (500, 50, 5 µg g?1) using oxide powders or element solutions, and are named ARM‐1, 2 and 3, respectively. We further document that sector‐field (SF) ICP‐MS (Element 2 or Element XR) is capable of sweeping seventy‐seven isotopes (from 7Li to 238U, a total of sixty‐eight elements) in 1 s and, thus, is able to quantify up to sixty‐eight elements by laser sampling. Micro‐ and bulk analyses indicate that the glasses are homogeneous with respect to major and trace elements. This paper provides preliminary data for the ARM glasses using a variety of analytical techniques (EPMA, XRF, ICP‐OES, ICP‐MS, LA‐Q‐ICP‐MS and LA‐SF‐ICP‐MS) performed in ten laboratories. Discrepancies in the data of V, Cr, Ni and Tl exist, mainly caused by analytical limitations. Preliminary reference and information values for fifty‐six elements were calculated with uncertainties [2 relative standard error (RSE)] estimated in the range of 1–20%. 相似文献
36.
Self-sustained oscillations at Volcán de Colima (México) inferred by Independent Component Analysis 总被引:2,自引:1,他引:1
We have analyzed Long-Period (LP) seismic events of Volcán de Colima (Mexico) recorded by four three-component broad-band
seismometers during January 2006. Frequency-domain analysis shows spectra mainly peaked in the range 0.3–2 Hz and characterized
by a monotonic decreasing envelope, as those produced in a cylindrically-symmetric self-oscillating cavity interacting with
a confined jet. Independent Component Analysis, a time-series decomposition method, extracts two or three nonlinear oscillation
modes depending on the station, with the fundamental one peaked at 0.4–0.5 Hz. These decomposed waves have a well defined
spectral content and are self-sustained oscillations with low dimensionality, as shown by dynamic system reconstruction methods.
Moreover, they show radial polarization in near field and transverse polarization in far field in North-West South-East direction.
Finally, we hypothesize a branched plumbing system with two principal conduits having alignments orthogonal to one another. 相似文献
37.
Chemical, modal and mineralogic data and textural observations suggest that the small mafic-ultramafic body at Predazzo, consisting of olivine-bearing gabbro, clinopyroxenite and quartz-bearing gabbro, is the result of a flow differentiation mechanism acting on a mush formed of 60% solid plus 40% liquid. Such a mechanism was capable of producing the concentration of the early formed crystals () towards the center of the body (clinopyroxenite) with segregation of two portions enriched in liquid toward the margins (olivine- and quartz-bearing gabbros). 相似文献
38.
Claudio Gheller Ornella Pantano & Lauro Moscardini 《Monthly notices of the Royal Astronomical Society》1998,295(3):519-533
We present a hydrodynamical code for cosmological simulations which uses the piecewise parabolic method (PPM) to follow the dynamics of the gas component and an N -body particle–mesh algorithm for the evolution of the collisionless component. The gravitational interaction between the two components is regulated by the Poisson equation which is solved by a standard fast Fourier transform (FFT) procedure. In order to simulate cosmological flows we have introduced several modifications to the original PPM scheme which we describe in detail. Various tests of the code are presented including adiabatic expansion, single and multiple pancake formation and three-dimensional cosmological simulations with initial conditions based on the cold dark matter scenario. 相似文献
39.
R. Devoti C. Ferraro E. Gueguen R. Lanotte V. Luceri A. Nardi R. Pacione P. Rutigliano C. Sciarretta F. Vespe 《Tectonophysics》2002,346(3-4)
During the Neogene and Quaternary, the western Mediterranean geodynamics was apparently dominated by the nearly eastward migration of the Apenninic arc and the associated opening (spreading) of the back-arc basin (Tyrrhenian Sea). However, during the last 5 My, the collision of the arc with the Apulian platform led to a dramatic change in the tectonic setting of the area. As geological processes require a long period of time to register the displacements of the different blocks, it is indispensable to take into account the present-day motion given by space geodesy data analysis in order to better constrain the geological models.Geodetic motions were derived from Global Positioning System (GPS), Satellite Laser Ranging (SLR) and Very Long Baseline Interferometry (VLBI) observations collected from different networks. All the geodetic solutions have been computed and combined at the Centre of Space Geodesy (CGS), at Matera, Italy.The geodetic results show a NNE motion of the Adriatic plate with a small component of counter-clockwise rotation, in good agreement with the geological and geophysical observations.In the southern Tyrrhenian area, the lengthening of the Matera–Cagliari baseline should imply that convergence cannot be considered as the driving mechanism for the Apenninic subduction process. The estimated motion of Noto is in quite good agreement with the estimated motion of the African plate. 相似文献
40.
The seventh part of the catalogue of Shakhbazian groups contains the positions and references of all the galaxies of the following 48 groups (north of δ > +2°30′): Shkh 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 142, 149, 150, 153, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166. For the estimation of the coordinates the Digitized Sky Survey was used. 相似文献